IMPROVED ELISA AND DOT-BLOT METHODS FOR THE DETECTION OF WHEY PROTEINS IN MEAT-PRODUCTS

Two techniques, ELISA and dot-blot, were applied to the qualitative detection of very low levels of whey proteins in liver pates. The use of an avidin-biotin amplification system for both methods led to a useful improvement of the detection limit. The detection level which was 4 g kg-1 with the classical ELISA method was improved to 1 g kg-1 with the amplified ELISA method. Using the dot-blot technique, the results showed that the minimum detectable level was 1.7 g kg-1 for the classical method with nitrocellulose (NC), 0.7 g kg-1 for the amplified method with NC, 0.7 g kg-1 for the classical method with cyanogen bromide-activated NC (activated NC) and 0.3 g kg-1 for the amplified method with activated NC.